I feed my 3 red bellys beefheart, i buy it at my local pet store and it cost about $4 for a package, it comes frozen and I just stick it in my freezer until feeding time, my piranhas love it, they eat it frozen! its gone in less than 30 seconds, i sometimes feed them rosys to, they eat these fish in one bite and they love to chase them, they are after all predators!